Door mat



FIG. 1 is a perspective view of a door mat, showing my new design;

FIG. 2 is a top plan view thereof;

FIG. 3 is a bottom plan view thereof;

FIG. 4 is a front view thereof, the rear view being a mirror image thereof; and,

FIG. 5 is a left side view thereof, the right side view being a mirror image thereof.

The broken lines shown in FIG. 3 depicts portions of the door mat that form no part of the claimed design. 

CLAIM The ornamental design for a door mat, as shown and described. 